1. Field of the Invention
The present invention relates to an apparatus for recording and reproducing a still image from, for example, a still video camera, and more precisely, it relates to a recording method of a i.e., still video apparatus (still image recording and play-back apparatus) in which sound signals can be recorded and reproduced.
2. Description of Related Art
In a still video apparatus, a unit of one or two recording tracks, out of a plurality of recording tracks provided on a magnetic disc, forms one field picture plane or one frame picture plane. In a still video apparatus in which sound signals can be recorded, a sound lasting from 5 to 20 seconds can be recorded on one track. Since one turn of the magnetic disc corresponds to one field of the image signal (about 1/60 second in the case of an NTSC system), upon recording, sound signals to be recorded within a predetermined time are first stored in a memory means, and then, the time base of the stored sound signals are compressed so that they may be read and recorded on the magnetic disc. Accordingly, a known still video apparatus is usually provided with an image release switch which is actuated to record a picture, a sound collecting switch which is actuated to store a sound in the memory means, and a sound release switch which is actuated to record the stored sound onto the magnetic disc.
In a recent still video apparatus, a recording system in which the image signals and the sound signals are recorded in a corresponding fashion has been adopted, which system will be referred to hereinafter as an AV (Audio-Visual) mode. In this AV mode type of recording lo system, for example, the tracks of the magnetic disc for the image signals and the sound signals are preset, so that when the image signals or the sound signals are recorded, data signals including the corresponding sound signals or image signals and discrimination marks which differentiate the presence of the corresponding image signals or sound signals, are recorded on the respective tracks. Upon reproducing the sound and image signals, the discrimination marks are reproduced to carry out the necessary operations in accordance with the reproduced discrimination marks. The data signals are subject to DPSK modulation and overlapped on the image signals so as to be recorded together.
In a known first recording method in the AV mode, first the storage of the sound signals in the memory means commences, and when the image release switch is actuated during the storage of the sound signals, the image signals are recorded. When the storage of the sound signals is complete, the stored sound signals are recorded.
In a known second recording method in the AV mode, when the image release switch is actuated, the image signals are first recorded, and thereafter, the storage of the sound signals automatically begins. When the storage of the sound signals is complete, the stored sound signals are automatically recorded.
However, in the first recording method, since the image signals are recorded during the storage of the sound signals, sounds produced when the diaphragm or shutter are driven upon operation of the image release switch may be recorded as noise, or the sound signals can be deteriorated by a fluctuation of the sound signal level due to a voltage drop caused by the commencement of the magnetic disc rotation or the emission of strobe light.
In the second recording method, since the sound signals are automatically recorded after the image signals are recorded, undesirable sound may be recorded, or conversely, desirable sounds may not be recorded.
Furthermore, in both the first and second recording methods, since the sound signals are recorded to correspond to the recorded image signals in the AV mode, in order to stop the recording of the sound signals after the completion of the recording of the image signals, it is necessary to actuate a mode selection switch to switch to the AV mode. To this end, to continuously record the image signals without temporarily recording the sound signals in the AV mode, the mode selection switch must be troublesomely actuated.
In addition to the foregoing, in the known recording methods mentioned above, after-recording in which the sound is recorded after the picture is recorded in the AV mode without changing the mode cannot be effected. Accordingly, it is necessary to record only the image signals in the normal mode, and then record the sound signals on the tracks of the corresponding image signals. This is troublesome.
The primary object of the present invention is to provide a recording apparatus and method which can eliminate the above mentioned drawbacks of the prior art.